1. Field of the Invention
This invention relates generally to digital systems, and, more particularly, to voltage regulation of components within a digital system.
2. Description of the Related Art
In the field of electronics, designers have been continuously reducing the size of components, such as transistors on a semiconductor chip, to increase the speed and performance of the electronic circuits, and to more efficiently utilize semiconductor real estate. For example, only a few years ago, a microprocessor was made up of less than one million transistors; however, recently microprocessors have been constructed with more than eight million transistors. This greatly increased number of components has necessarily increased the amount of heat dissipated by modern microprocessors. To ensure stable operation of a microprocessor, manufacturers commonly require that they be maintained within a preferred temperature range. That is, cooling, such as by forced-air ventilation, is standard in modern computer systems.
A voltage regulator is commonly used with a microprocessor in a conventional computer system to precisely control the voltages provided to the microprocessor and other components within a computer system. Conventional voltage regulators are also responsible for generating substantial heat, which can exacerbate the cooling problems of the modern computer system. Moreover, with reduced component size and reduced voltage rails, the voltage margin is reduced. That is, modern microprocessors require a closely controlled voltage supply. However, the voltage regulator's ability to precisely control voltage levels is also dependent upon temperature. That is, an overheated voltage regulator may not produce an output voltage within the desired operating range of the microprocessor.
Accordingly, to aid in cooling a conventional computer system, the voltage regulator is commonly positioned a considerable distance from the microprocessor. However, separating the voltage regulator from the microprocessor generally reduces the ability of the voltage regulator to closely control output voltage. As the electrical connections that deliver power between the microprocessor and voltage regulator become longer, the ability to tightly regulate the voltage becomes difficult. Additionally, the use of longer lines within a system may hinder the routing efficiency of a computer system because of the limited amount of system real estate available for routing signals. Thus, remote voltage regulation requires that the output voltage be even more precisely controlled to account for variations introduced by the increased distance. More precise control of the output voltage generally equates to increased cost and reduced efficiency.
The present invention is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.